JPH03292705A - Ferromagnetic film and magnet head using thereof - Google Patents

Abstract

PURPOSE:To obtain a material for magnetic heads which can maintain saturated magnetic flux density and soft magnetic characteristics to a high temperature and has high reaction-resisting property and high corrosion-resisting property by a method wherein an oxide is mixed into ferromagnetic metal. CONSTITUTION:A piece of ferromagnetic metal, mainly composed of Fe and Co, and the targets of a oxide are alternately sputtered on a crystallized glass substrate 1 using an ion beam sputtering device, a laminated film consisting of a ferromagnetic metal layer 2 and an oxide layer 3 is manufactured, and a heat treatment is conducted for an hour in an Ar gas atmosphere. A heat-proof high saturation magnetic flux density film excellently maintains its soft magnetic characteristics at least up to 600 deg.C, and its saturation magnetic flux density is not decreased. Also, not only the soft magnetic film has exceedingly excellent corrosion-resisting property but also the reaction layer such as an oxide and the like is hardly formed on the interface between the magnetic film and ferrite. Accordingly, when the heat-proof high saturation magnetic flux density film is used for the magnetic head of a magnetic recording device, especially, when it is used on a metal-in-gap type magnetic head, a glass bonding operation can be conducted at a high temperature, and a glass layer having sufficient strength can be formed.

Description

[Detailed description of the invention]

[0001]

[Industrial application field]

The present invention relates to a magnetic head material used in magnetic disk drives, VTRs, etc., and in particular has high saturation magnetic flux density, high magnetic permeability,
The present invention relates to a multilayer magnetic film having high heat resistance, high corrosion resistance, and high reaction resistance, and a magnetic head using the same. [0002]

[Conventional technology]

In recent years, magnetic recording technology has made remarkable progress, and recording density is being improved. In order to increase the recording density, it is necessary to use a recording medium with a high coercive force, and in order to magnetize a recording medium with a high coercive force, a magnetic pole material having a high saturation magnetic flux density is required. For this reason, Ni--Fe alloy (permalloy) and Co-based amorphous alloy thin films are beginning to be used as magnetic pole materials in place of conventional ferrite and the like. Furthermore, in addition to having a high saturation magnetic flux density, the magnetic pole material is required to have a high magnetic permeability in order to improve recording and reproducing efficiency. It is also required to have heat resistance that can withstand the glass filling heating process in the process of forming a magnetic head and maintain high magnetic permeability. [0003] As such a magnetic pole material, Japanese Patent Application Laid-Open No. 62-210607
As shown in the issue, metals selected from Fe, Co, Ni, and Mn include Nb, Zr, Ti, Ta, HfCr, and W.
, a material to which Mo and nitrogen are added simultaneously has been reported. The method for producing this material is to sputter a metal target having a predetermined composition using a mixed gas of argon and nitrogen as a sputtering gas. According to this report, by modulating the nitrogen concentration in the sputtering gas and alternately stacking nitrided and non-nitrided layers, a film with saturation magnetic flux density of 1.5T and coercive force of 10e or less can be obtained. There is. The coercive force of this film was kept as low as 600°C, and the heat resistance was 600°C. [0004] Also, Institute of Electronics, Information and Communication Engineers MR89-12 (1989, 7
) by simultaneously adding Ti, Zr, Hf, and C to Fe to form an Fe-based amorphous film, and then heat-treating this, a microcrystalline soft magnetic material with high heat resistance can be obtained. It was shown that [0005]

[Problem to be solved by the invention]

The present inventors sputtered Fe--Nb, Fe--Ta, and Fe--Hf based materials in a mixed gas of argon and nitrogen, and conducted additional trials and experiments based on the above-mentioned report. As a result,
As reported, the coercive force remains 1 even when heated at 400 to 600 degrees Celsius.
It was confirmed that it showed a low value of 0e or less. Also, Fe
It was also confirmed that a multilayer magnetic film with a coercive force of 10e or less could be obtained by sputtering a -Hf-C based material in argon gas and then heat-treating it at 500 to 600°C. [0006] However, the present inventors formed these conventional materials on a Mn-Zn ferrite single crystal substrate and used 6
When a metal-in-gap head was prototyped through a heating process at 00°C, it was found that the Mn-Zn ferrite single crystal substrate and the magnetic film reacted to form an oxide layer at the interface. At this time, as a result of examining the recording and reproducing characteristics of the magnetic head, as expected, a large pseudogap signal was observed due to the nonmagnetic layer at the interface between the crystal substrate and the magnetic film. If such a pseudo gap signal is observed, normal recording and reproduction cannot be performed. At this time, a reaction between the magnetic film and the filled glass was also observed, and it was found that the magnetic film had become thinner. In other words, although conventional magnetic films exhibit excellent soft magnetic properties as a single magnetic film,
It has been confirmed that when manufacturing a magnetic head that involves a glass bonding process, preventing reactions with the substrate or the filled glass becomes a problem. [0007] On the other hand, when we evaluated the corrosion resistance of a sample formed on a glass substrate as a dummy sample by subjecting it to a salt spray test, a test, and a constant temperature and humidity test, we found that the conventionally used sendust film and Co-Nb-Zr It is extremely susceptible to corrosion compared to other types of films, and its use as a magnetic head was questioned. [0008] Accordingly, it is an object of the present invention to provide a new magnetic herad material that overcomes the drawbacks of the prior art mentioned above. [0009]

[Means to solve the problem]

The inventors of the present invention have continued to conduct intensive research in order to solve the above-mentioned problems, but by mixing oxides into ferromagnetic metals, the saturation magnetic flux density and soft magnetic properties are maintained even at high temperatures. Furthermore, we were able to develop a magnetic head material that has high reaction resistance with oxides such as ferrite and glass, and also has high corrosion resistance. Here, the oxides are Hf-0, Nb-0
, Ta -0, Ti -0, Zr -0, V-0, W-
It is a substance consisting of IVa and VIa group elements having bonds such as 0 and Mo-0, and oxygen. In addition, additives may be added to improve the magnetic properties. In particular, addition of B, C, N, and P is effective for improving soft magnetic properties. In addition, to improve corrosion resistance, Ni, RhRu, Pd, Zr, N
b, Ta, Ag, Os, Ir, Pt, Au, Cr, M. Addition of W and Ti is effective. [0010] In the multilayer magnetic film of the present invention, an oxide phase is mixed in the metal phase. There are no restrictions on the method of mixing oxides, and even if oxides are not present during the formation of the magnetic film, they may be generated by heat treatment or the like. Alternatively, it can be mixed in the form of an oxide in advance during the formation of the magnetic film. For example, any method is possible, such as lamination of a metal layer and an oxide layer, lamination of a metal layer and elements constituting the metal and oxide, or simultaneous deposition of metal and elements constituting the oxide. [0011] By using the multilayer magnetic film of the present invention in the magnetic core of a magnetic head of a magnetic recording device, a magnetic recording device with excellent recording and reproducing characteristics can be obtained. In particular, even greater effects can be obtained by applying the multilayer magnetic film of the present invention to a magnetic head made by a method including a glass bonding process, such as a metal-in-gap type head. [0012]

[Effect]

As mentioned above, by mixing oxides into a ferromagnetic metal film, the saturation magnetic flux density and soft magnetic properties can be maintained up to high temperatures, but the mechanism is not necessarily clear enough. However, as a result of studies conducted by the present inventors, even when heated up to 600°C, the multilayer magnetic film containing these oxides does not show any coarsening of the crystal grain size, and the oxides remain in the multilayer magnetic film. It was confirmed that the diffusion of the constituent elements of the magnetic film was suppressed and the growth of crystal grains due to heating was prevented. At this time, the film heated to 600°C was subjected to high-resolution EP
MA (Electron Probe Micro
As a result of analysis using the analysis method, an oxide phase was observed around the crystal grains that make up the multilayer magnetic film, and the presence of this phase suppressed the grain growth (coarsening) of the crystal grains that made up the multilayer magnetic film. It was observed that Except for materials with a magnetocrystalline anisotropy constant close to zero, the soft magnetic properties of ferromagnetic materials are related to the size of the crystal grains that make up the ferromagnetic material, and the soft magnetic properties deteriorate as the crystal grains increase. It is known. Therefore, it is considered that in the multilayer magnetic film of the present invention, the crystal grains were similarly kept small even at high temperatures, so that the soft magnetic properties did not deteriorate. However, when the same film was examined by X-ray diffraction, no oxides could be detected, and these substances were either trace amounts or amorphous. [0013] Furthermore, the saturation magnetic flux density of the multilayer magnetic film of the present invention showed a tendency to decrease as the amount of added oxide increased, but this was due to the effect of simple dilution of the magnetic material by the addition of non-magnetic material. It is assumed that this is due to the following. [0014]

【Example】

Examples of the present invention will be given below and will be explained in more detail with reference to figures and tables. [Example 1] A multilayer magnetic film containing Fe and Co as main components was formed on a crystallized glass substrate using an ion beam sputtering device. The ion beam sputtering apparatus used in this example is equipped with two ion guns, one of which can sputter a target and deposit sputtered particles onto a substrate. On the other hand, the substrate can be cleaned, etc. The target holder of this device is rotary and can be loaded with up to four types of targets, and any target can be selected for sputtering. Therefore, any laminated film composed of these target materials can be formed. Such devices are known (Journal of Applied Physics).
APPLIED PHYSIC3) Vol, 611
5 June 1987 No. 12). Using this equipment, ferromagnetic metals mainly composed of Fe and Co and oxide targets are sputtered alternately to produce a laminated film. Sputtering was performed under the following conditions. [0015] Sputtering gas・・Ar Ar gas pressure in the device・2.5×1O−2Pa ion gun acceleration voltage for evaporation・・Ion gun ion current for 800 layer evaporation・120 mA target substrate distance・1
30 mm substrate temperature: 50 to 100° C. A cross-sectional view of the laminated film produced under the above conditions is shown in FIG. In this example, a crystallized glass substrate is used as the substrate 1, and the layer thickness is 9.
A laminated film consisting of a ferromagnetic metal layer 2 with a thickness of 1 nm and an oxide layer 3 with a thickness of 1 nm was produced. The thickness of the entire laminated film was 1 μm, so the ferromagnetic metal layer 2 had 100 layers and the oxide layer 3 had 99 layers.
It became a layer. [0016] The obtained laminated film was heat-treated in Ar gas at a temperature of 100°C to 700°C for 1 hour, and the soft magnetic properties of each film were evaluated, the crystallographic evaluation was performed by X-ray diffraction, and the oxide was determined by analysis. I checked the layers. [0017] Table 1 shows the results. [0018]

[Table 1] [0019] In the table, the ferromagnetic metal film and oxide indicate the composition of the target during film formation. In an ideal film formation process, it can be considered that the composition of the target is approximately equal to the composition of the film to be formed. However, depending on the conditions, light elements may be repelled from the substrate surface, resulting in the composition of the film being lower than that of the target. Coercive force, corrosion test, and test are values measured after heat treatment at 500° C. for 1 hour. Note that the coercive force was measured using a B-H curve tracer. Heat resistance was indicated at the temperature at which the coercive force of the heat-treated sample was 1.50e or more. Further, the corrosion test is the result of a salt water spray test in which the temperature was maintained at 35° C. while intermittently spraying a 0.5% NaCl aqueous solution, and the time taken for corrosion to progress by 5% is the result. Here, a 5% decrease in film magnetization means a 5% decrease in corrosion.
It is defined as progressing. [00201 As a result, a ferromagnetic metal film containing Fe and Co as main components was
By laminating layers through oxides of Va and VIa group elements, it was possible to obtain a multilayer magnetic film having excellent soft magnetic properties with a coercive force of 1.50 e or less even at a high temperature of 600°C. The corrosion test results at this time confirmed that all samples exhibited corrosion resistance for 50 days or more. In addition, similarly Fe, Co
We also investigated the fabrication of a multilayer film in which elements such as B and CN were added to improve soft magnetic properties to a ferromagnetic metal film whose main component is B, but a decrease in coercive force of 5 to 15% was observed. Otherwise, the corrosion resistance was almost the same. The present inventors have proposed B, N, C, P (7) in Japanese Patent Application Laid-open No. 63-65604.
It is shown that the effect of reducing coercive force can be obtained by adding 5 to 20 at %, and it is presumed that a similar effect is obtained. In addition, these ferromagnetic metals are further coated with Ni and R.
h, Ru, Pd, ZrNb, Ta, Ag, Os, Ir,
Pt, Au, Cr, Mo, W, Ti, Bi. Further improvement in corrosion resistance can be expected by adding one or more elements selected from V, Co, and Cu. Regarding the effects of these additive elements, the present inventors reported in JP-A-63-2
It is disclosed in No. 36304.

As a comparative experiment in February, a multilayer film was formed using borides, carbides, and nitrides of IVa and VIa group elements instead of oxides. However, these films were found to have extremely low corrosion resistance. In other words, when borides, carbides, and nitrides are inserted, these substances tend to change into oxides with lower energy, so when exposed to salt water in the air for a long time,
It is assumed that it oxidizes and corrodes. Also, Fe, Co
If a film of 1 μm is formed by just using
Coarse grains occur at 0°C, and the coercive force is 50
It increased by more than e. Therefore, Ti, Zr, Hf, V, N
It is clear that heat resistance and corrosion resistance are improved by inserting an oxide material such as bTa or Cr into a ferromagnetic metal film. [0022] As a result of observing the cross-sectional structure of the laminated film heat-treated at 600°C using an electron microscope, it was found that the laminated structure was maintained even after the heat treatment at 600°C. It can be seen that grain growth is suppressed. The present inventors also laminated these ferromagnetic metal films via different metal films such as Ni and Cr instead of oxide, and
After heat treatment at 00°C, the cross-sectional structure was observed using an electron microscope. As a result, the ferromagnetic metal film and the intermediate layer metal film were completely diffused into each other, and not only was it not possible to recognize a laminated structure, but the crystal grains were In some cases, the film became coarse and became a single single crystal from the surface of the film to the interface of the substrate. [0023] There is no particular limit to the thickness of the intermediate film of the present invention, but as mentioned above, when the proportion of the non-magnetic intermediate film in the film increases,
This is not preferable because the saturation magnetic flux density decreases due to the effect of simple dilution. From this point of view, it is better for the interlayer film to be as thin as possible. However, as disclosed in JP-A No. 59-9905, by laminating a crystalline ferromagnetic metal film and a different type of intermediate layer, the crystal structure of the ferromagnetic metal film can be made finer and suitable magnetic properties can be obtained. It will be done. In order to expect such an effect from the intermediate layer, it is necessary that the thickness of the intermediate layer be 1 nm or more. When an intermediate layer with a thickness of 1 nm or more and a ferromagnetic metal layer are laminated by sputtering, the crystal structure of the ferromagnetic metal layer becomes finer, and even if it is heated, the oxide of the intermediate layer will not form in the ferromagnetic metal layer. It is thought that it invades the grain boundaries and prevents crystal coarsening. [0024] As a result of examining the magnetic film of the present invention by X-ray diffraction method, 6
The crystal structure of the film heat-treated at 00°C is a body-centered cubic structure when Fe is the main component, and when CO is the main component,
It had a hexagonal close-packed structure. In both cases, Fe and Co were in a single phase with no other crystal structure. Therefore, Fe and Co
is a non-ferromagnetic material with other crystal structure (e.g. γ-Fe,
A high saturation magnetic flux density of 1.7 T or more could be obtained even after heat treatment at 600° C. or higher without producing FeC2Fe203). [0025] [Example 2] A target in which oxygen is added to a ferromagnetic metal, and IVa, V
A laminated film was formed in the same manner as in Example 1 using a group Ia metal target. Targets made by adding oxygen to ferromagnetic metals include Fe mixed with Fe2O3, and CO mixed with CoO.
Created by mixing. The results obtained are shown in Table 2. [0026] [Table 2] (Table 2) [0027] In the table, the multilayer magnetic film and metal indicate the composition of the target during film formation. Further, the coercive force and crystal grain size are values measured after heat treatment at 600° C. for 1 hour. Note that the corrosion resistance was determined by the salt water spray test in the same manner as in Example 1. [0028] As a result, a coercive force of 1.10 can be achieved even at a high temperature of 600° C. by laminating ferromagnetic metal films containing oxygen-added Fe and Co as main components via metals of group IVa and VIa elements.
A multilayer magnetic film with excellent soft magnetic properties of less than e could be obtained. [0029] It was confirmed that the crystal grain size at this time was maintained at 200A or less. Since the crystal grain size before heat treatment was 150A or less, it became clear that the crystal grain size hardly changed due to heat treatment. However, when we investigated the change in coercive force due to heat treatment, we found that the coercive force increased once in the range of 300°C to 450°C, and then decreased again as the temperature was further increased. The results were different from those obtained by laminating the two layers with each other. [00301 The change in saturation magnetic flux density due to heat treatment was the same as in Example 1, and no significant change was observed. In particular, there was no decrease in saturation magnetic flux density above 600°C. [0031] As a result of observing the cross-sectional structure of the laminated film heat-treated at 700° C. using an electron microscope, it was found that the laminated structure was maintained even after the heat treatment at 700° C., and that the laminated structure facilitated the growth of crystal grains in the ferromagnetic metal film. I can see that it is suppressed. Furthermore, as a result of analyzing these ferromagnetic metal laminated films by high-resolution EPMA method, the present inventors found that the oxygen added to the multilayer magnetic film also gathered at the location of the metal layer inserted as an intermediate layer, and the oxide is thought to be formed. It was also confirmed that a portion of the inserted metal had diffused and was present so as to surround the crystal grains that constitute the multilayer magnetic film. Added carbon or boron is also present here, and it is thought that carbides and borides are also present at the same time. The film formed by sputtering and the film after heat treatment at 600°C were subjected to XP
S (Xray Photoelectron 5pe
Analyzed by ctroscopy. As a result, the peak indicating the metal element constituting the intermediate layer, which was observed in the film before heat treatment, became smaller after the heat treatment, and instead, a peak indicating the presence of the oxide of the element constituting the intermediate layer was observed. That is, it was confirmed that oxygen and the metal of the intermediate layer were in a bonded state (ie, oxide) in the multilayer magnetic film after heat treatment. Therefore, it is clear that the heat resistance can be improved by allowing the oxide to exist around the crystal grains constituting the ferromagnetic metal film. The obtained magnetic film was tested for corrosion resistance in the same manner as in Example 1, and as a result, all samples showed corrosion resistance for 50 days or more, and the presence of oxides in the magnetic film prevented corrosion. It became clear. [0032] In Example 2, as in Example 1, other elements may be added to reduce coercive force, improve corrosion resistance, and the like. Furthermore, the relationship between the intermediate layer and the ferromagnetic metal layer can be considered in the same manner as in Example 1. [0033] [Example 3] A multilayer magnetic film was created using the ferromagnetic metals shown in Table 3 as a target and using a sputtering gas as a mixed gas of argon and oxygen. [0034]

[Table 3] (Table 39 [0035] In the table, the multilayer magnetic film shows the composition of the target during film formation. Also, the oxygen concentration shows the oxygen concentration in the sputtering gas. The coercive force and corrosion resistance are 1 at 600°C. This is the value measured after heat treatment for several hours.The corrosion resistance is shown in Example 1.
It was measured in the same way as in the case of . As a result, by sputtering a ferromagnetic metal film mainly composed of Fe and Co to which IVa and VTa group elements were added,
It was possible to obtain a multilayer magnetic film with excellent soft magnetic properties with a coercive force of 10e or less even at a high temperature of 0°C. It was confirmed that the crystal grain size at this time was maintained at 200A or less. Since the crystal grain size before heat treatment was 1508 or less, it became clear that the crystal grain size was hardly changed by heat treatment. [0036] Furthermore, the corrosion resistance of the films heat-treated at 600° C. was 50 days or more, and compared to the corrosion resistance of a magnetic film that does not contain oxygen, which is 10 to 30 days, it is clear that the corrosion resistance of the films heat-treated at 600° C. We were able to improve this. [0037] When the amount of oxygen contained in the magnetic film after heat treatment was measured by the EPMA method, it was confirmed that 5.2 to 8.4 at % of oxygen was present in the film. In order to examine the influence of oxygen content in more detail, we sputtered a Fe86Nb1oB4 film while changing the oxygen concentration in the sputtering gas. As a result, the relationship between oxygen content, coercive force, and corrosion resistance was as shown in FIG. 2. That is, in order to keep the coercive force low, the oxygen concentration in the film should be 15 at% or less, more preferably 10 at%.
It was found that the condition is t% or less, and that corrosion resistance improves with the addition of oxygen. In addition, in order to obtain the desired results of coercive force of 20e or less and corrosion resistance of 50 days or more,
It has been found that the condition is that the oxygen concentration in the film is 0.1 at% or more and 15 at% or less. [0038] As a result of observing the cross-sectional structure of the magnetic film heat-treated at 600°C using an electron microscope, it was found that the crystal grain size was maintained at less than 200A even after the heat treatment at 600°C, indicating that the formation of oxides was caused by the formation of ferromagnetic metal films. It can be seen that the growth of crystal grains is suppressed. Furthermore, the present inventors have developed these ferromagnetic metal films using high-resolution E
As a result of analysis using the PMA method, I
It was confirmed that oxides of Va and VIa group elements were present. Therefore, as in Example 2, it is clear that heat resistance and corrosion resistance can be improved by having a high melting point material such as an oxide around the crystal grains constituting the ferromagnetic metal film. [0039] Also in Example 3, additive elements can be selected in the same manner as in Example 1.2. [0040] [Example 4] As shown in FIG. 3, a magnetic pole of a metal-in-gap head was manufactured using the multilayer magnetic films obtained in Examples 1 to 3, and evaluated as a head of a high-density magnetic recording device. did. FIG. 3A shows an overall perspective view, and FIG. 3B shows an enlarged view of the vicinity of the gap. M n -Z n ferrite substrate 4 has a film thickness of 5
The magnetic cores to which the multilayer magnetic film 5 of .mu.m is deposited are butted against each other to form a gap 8. The gap length is 0.3 μm. A coil 7 is provided in the magnetic core. The glass bonding temperature during head formation was 520°C. The medium used had a coercive force of 15000e. As a result, the recording characteristics of the head using the Fe-based multilayer magnetic film of the present invention for the magnetic pole of the head are 4.
．． The improvement was 6 dB, and the playback output was approximately 3 dB higher. Furthermore, a recording density of 100 kBPI or more could be obtained. This is because the multilayer magnetic film of the present invention has a higher saturation magnetic flux density than other materials. [0041] Further, as a result of measuring the pseudo signal output due to the pseudo gap effect of the head, it was found that Nb, Zr, Ti
, Ta, Hf, Cr, W, Mo, and nitrogen or carbon added at the same time as the magnetic pole of the head, a spurious signal output of 3 to 5 dB was detected; When used, it was confirmed that the pseudo signal output was reduced to 2 dB or less. When the glass adhesive part of the obtained head was peeled off and depth analysis was performed using Auger electron spectroscopy from the magnetic film side toward the ferrite, it was found that in the conventional head, 50 to 180 A of oxidation was observed at the interface between the magnetic film and the ferrite. The existence of a layer was confirmed. On the other hand, in the head of the present invention, the thickness of the oxide layer at the interface between the magnetic film and the ferrite is at most 20A, and if an oxide phase exists in the magnetic film, the thickness of the oxide layer at the interface becomes thinner, resulting in false signals. It became clear that the output was reduced. [0042] Furthermore, when a conventional magnetic film is used for the magnetic pole, a reaction occurs between the magnetic film and the filler glass during glass bonding, and a part of the magnetic film changes to a film with poor soft magnetic properties, causing the recording/reproduction of the head to deteriorate. properties deteriorated. Furthermore, in severe cases, a film with a high coercive force may be formed, erasing signals previously recorded on the medium. However, in the present invention, no formation of a reaction layer was observed even when the interface between the magnetic film and the filled glass was observed using an optical microscope, and high recording and reproducing characteristics were exhibited. [0043] In the above examples, the magnetic film was formed by the ion beam sputtering method, but the present inventors have also conducted a similar study using the RF sputtering method, and the substrate temperature was
It was confirmed that a magnetic film having almost the same magnetic properties and heat resistance could be changed by simply raising the temperature to around 0°C. Therefore, the present invention is effective regardless of the film formation method. [0044]

【Effect of the invention】

As explained in detail above, the heat-resistant high saturation magnetic flux density film according to the present invention has good soft magnetic properties up to a temperature of at least 600° C., and there is no decrease in the saturation magnetic flux density. In addition, this soft magnetic film not only has extremely excellent corrosion resistance, but also prevents the formation of reaction layers such as oxides at the interface between the magnetic film and ferrite. When used in heads, particularly metal-in-gap magnetic heads, glass bonding can now be performed at high temperatures of 500° C. or higher, and a glass layer with sufficient strength can be formed. Further, the pseudo signal output based on the pseudo gap was also a low value of 2 dB or less.

[Brief explanation of drawings]

[Figure 1] Figure 1 is a cross-sectional view of the ferromagnetic metal film of the present invention.

[Figure 2]
Figure 2 is a graph showing the influence of oxygen concentration in the film on the coercive force and resistance to fragility of the multilayer magnetic film of the present invention.

FIG. 3A is a perspective view of the magnetic head of the present invention, and B is a plan view showing the vicinity of the gap portion of the magnetic head of the present invention.

[Explanation of symbols]

1...Substrate 1.2...Ferromagnetic metal layer, 3...Oxide layer

[Document name] Drawing

[Figure 1] (figure )

[Figure 2] (Figure 2 )

[Figure 3] (Figure 3 ) (B)

Claims (23)

[Claims] [Claim 1] A ferromagnetic film characterized by the presence of an oxide phase in a ferromagnetic metal. 2. The ferromagnetic film according to claim 1, wherein the oxide phase contains at least one element selected from group IVa, Va, and VIa elements. 3. The ferromagnetic film according to claim 1, wherein the ferromagnetic metal excluding the oxide phase is a single-phase crystal. 4. Claims 1 to 3, wherein the ferromagnetic metal is made of a crystal containing Fe or Co as a main component.
A ferromagnetic film according to any one of the above. 5. The ferromagnetic film according to claim 4, wherein the average grain size of the crystals is 200 angstroms or less. 6. The ferromagnetic film according to claim 5, wherein the oxide phase is present at a grain boundary portion of the crystal. 7. The amount of oxygen added to the ferromagnetic metal is 0.
．． 7. The ferromagnetic film according to claim 1, wherein the ferromagnetic film has a content of 1 to 15 at%. 8. The ferromagnetic film according to claim 1, further comprising one or more additional elements added to improve magnetic properties or corrosion resistance. 9. The ferromagnetic film according to claim 8, wherein the additive element is at least one element selected from the group consisting of B, N, C, and P. 10. Ferromagnetic metal layer, IVa, Va, VIa
A multilayer magnetic film comprising a stack of intermediate layers containing at least one oxide selected from group elements. 11. The multilayer magnetic film according to claim 10, wherein the ferromagnetic metal layer contains Fe or Co as a main component. 12. The ferromagnetic metal layer further comprises B, N, C,
The multilayer magnetic film according to claim 11, containing at least one element selected from the group consisting of P. 13. The multilayer magnetic film according to claim 10, wherein the intermediate layer has a thickness of 1 nm or more. 14. A ferromagnetic metal layer doped with oxygen, and an IVa
, Va, and VIa group elements. 15. The multilayer magnetic film according to claim 14, wherein the ferromagnetic metal layer contains Fe or Co as a main component. 16. The ferromagnetic metal layer further comprises B, N, C,
The multilayer magnetic film according to claim 15, containing at least one element selected from the group consisting of P. 17. The multilayer magnetic film according to claim 14, wherein the intermediate layer has a thickness of 1 nm or more. 18. A strong chemical containing at least one element selected from Fe and Co, at least one element selected from group IVa, Va, and VIa elements, and 0.1 to 15 at% oxygen in an oxide state. magnetic film. 19. A target containing at least one element selected from Fe and Co and a target containing an oxide of at least one element selected from group IVa, Va, and VIa elements are sputtered alternately. A method for manufacturing a ferromagnetic film forming a multilayer magnetic film. 20. A target containing at least one element selected from Fe, Co and oxygen; IVa, Va, VI
A method for manufacturing a ferromagnetic film, which comprises forming a multilayer magnetic film by alternately sputtering targets containing at least one element selected from Group A elements. 21. A ferromagnetic method in which a target containing at least one element selected from Fe and Co and at least one element selected from group IVa, Va, and VIa elements is sputtered in a sputtering gas containing oxygen. Membrane manufacturing method. 22. A magnetic circuit having a magnetic film formed by the presence of an oxide phase in a ferromagnetic metal, a coil magnetically coupled to the magnetic circuit, and a magnetic gap provided in a part of the magnetic circuit. A magnetic head with 23. The magnetic head according to claim 22, wherein the magnetic circuit is formed by bonding a pair of magnetic cores each having the magnetic film adhered to a substrate using glass.